1. Field of the Invention
The present invention relates to the measurement of digital radio frequency emissions, and particularly to an enhanced dynamic range RF pulse measurement system.
2. Description of the Related Art
When analyzing the Radio Frequency (RF) environment and RF signals, it is often necessary to accurately measure and record very low level RF signals in the presence of much higher level signals. Relative power levels can be as high as 70 decibels (dB), which, in power level terms, represents a range of over 10 million to one. This high instantaneous dynamic range can make it extremely difficult or impossible with currently available technology and test equipment to make precision power, frequency, signal characteristic, time and other measurements over such a large power range.
This challenge is compounded when the nature of the signals being analyzed includes RF pulses or other complex waveforms that have very fast rise and fall times, short durations, and/or rapidly varying power and/or frequency characteristics that must be captured and not distorted by the analysis system. This can simultaneously impose requirements for high instantaneous RF bandwidth capabilities that can be hundreds of Mega-Hertz (MHz) or more for many modern signals.
The laws of physics dictate that the amount of noise (thermal noise and noise from other sources) increases with instantaneous RF bandwidth. This noise is always unavoidably captured by all systems, along with desired signals. Background noise establishes a “noise floor” that serves to limit the maximum possible system analysis dynamic range. This noise floor can make it impossible to simultaneously achieve the signal analysis dynamic range and signal analysis instantaneous RF bandwidth needed to accurately measure the desired signal parameters. As a result, accurate measurements often cannot be made without highly undesirable compromises that can unacceptably limit system performance.
Thus, an enhanced dynamic range RF pulse measurement system solving the aforementioned problems is desired.